Infiniti M56

The Infiniti M is a luxurious four-door sport sedan, and it emphasizes a performance driving feel a bit more than some other cars in its class. Now badged the M37 (V-6), the M56 (V-8), or the M35h (Hybrid), the M sedans are all sized and priced to compete against the BMW 5-Series, Lexus GS, Jaguar XF, Acura RL, and Mercedes-Benz E-Class. For the latest, read our review of the 2013 Infiniti M. Now... Read More Below »

The Infiniti M is a luxurious four-door sport sedan, and it emphasizes a performance driving feel a bit more than some other cars in its class. Now badged the M37 (V-6), the M56 (V-8), or the M35h (Hybrid), the M sedans are all sized and priced to compete against the BMW 5-Series, Lexus GS, Jaguar XF, Acura RL, and Mercedes-Benz E-Class.

Now in its third generation, the M sedan was preceded in name only, by an unrelated M30 coupe and convertible that helped launch the Infiniti brand in the early 1990s. In 2003, the M45 sedan became the first Infiniti four-door to directly challenge the mid-size luxury sedans from Germany and Japan. A replacement for the droopy-profile J30 sedan, the M45 sported a V-8 engine shared with Infiniti's former luxury flagship, the Q45 sedan. This M was based on the Japanese-market Nissan Gloria, and was sold for three model years as the company prepared a more serious, stylish entry in the class.

That next generation sedan came in two flavors: M35 and M45. Introduced in the 2006 model year, the second M sedan brought a slightly more updated look and a very well-balanced chassis that offered all-wheel drive as an option, though most sedans were sold with rear-wheel drive. Based on the same platform that spawned the Infiniti G35 model range as well as the Nissan 350Z, the 2006-2010 Infiniti M earned praise for its handling and for the added V-6 model, which also shared the 350Z/G35 V-6 powertrain. Though it was smaller than the Q45, this M would eventually become the Infiniti flagship, as the brand discontinued the big Q sedan after the 2006 model year.

For the third-generation M sedans, Infiniti chose an especially expressive theme, inside and out, in the hopes of boosting the car's profile in its crowded traditional luxury segment, which expanded to include the Jaguar XF. First, the company showed a stunning concept dubbed Essence, and pitched it as the future theme for Infiniti vehicles. The production vehicle made its debut at the 2009 Los Angeles auto show, and subsequently went on sale in the spring of 2010.

Since then, the Infiniti M has risen toward the top of our ratings thanks to a brilliant V-8 powertrain, that Essence-inspired style, and surprising handling and rear-seat room. The striking sheetmetal is paired with a subtle interior with an option for silver-buffed wood trim, and the fit and finish are among the best in its class. The 400-horsepower V-8 engine teams with a seven-speed automatic and paddle shifters for 0-60 mph acceleration in the 5-second range; the M37's V-6 powertrain is nearly as quick, but noise and vibration are much less impressive. With the best steering and ride quality among its peers, the M sedan also sports a spacious back seat.

The M35h was new to the Infiniti M lineup for 2012. It gets a Direct Response Hybrid system that's more performance-oriented than most hybrid powertrains, and it produces more than 350 hp altogether yet is rated at 27 mpg city, 32 highway. Overall, in a first drive we found this model to have an elusive mix of fun-to-drive qualities and eco-friendliness, with steering and dynamics that felt nearly as good as those of the other models.

For 2013, Infiniti expanded availability of the Sport Package to all-wheel-drive models of the M37 and M56; it also wrapped more features into this package.A 20-inch performance tire and wheel package, including upgraded brakes, was also newly optional.